Polyaniline (PANI)/silver (Ag) nanocomposites containing PANI nanofibers decorated with well-dispersed Ag nanoparticles were obtained with interfacial polymerization. It was interesting that silver nitride affected not only the diameter and crystallinity of the PANI nanofibers but also their room-temperature conductivity. The conductivity increased with increasing Ag loading up to 10 (molar ratio of aniline to silver nitride), but the conductivity moderately decreased with further increasing Ag loading. Scanning electron microscopy and X-ray diffraction analysis results indicate that the diameter of the PANI nanofibers became smaller and smaller, and their crystallinity got better and better with increasing Ag loading. However, Fourier transform infrared analysis proved that the balance of oxidized and reduced units of PANI became big with increasing Ag loading, which may have resulted in the decreasing conductivity of PANI. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 26-31, 2010